An Illinois graduate and former football co-captain who is an astronaut is making a rare Christmas Eve spacewalk to repair the International Space Station's cooling system.

Michael Hopkins is a 1991 engineering graduate who was a defensive back on the football team from 1988-91. He received the Illini's special teams player of the year award in 1989.

Hopkins made the repairs Tuesday along with astronaut Rick Mastracchio.

NASA ordered up the spacewalks to revive a critical cooling loop at the International Space Station. All nonessential equipment had to be turned off when the line conked out Dec. 11, and many science experiments halted.

Mastracchio and Hopkins removed a faulty ammonia pump during Saturday's spacewalk. On Tuesday, they worked to install a new pump 260 miles above the planet.

Hopkins has been on the space station for about seven months in what is his first space flight.